An optically active phosphine ligand having a chiral center on a phosphorous atom plays an important role in a catalytically asymmetric synthesis reaction using a transition metal complex. A 1,2-bis(dialkylphosphino)benzene derivative has been suggested as an optically active phosphine ligand having a chiral center on a phosphorous atom, for example, in PTL 1. A transition metal complex having this benzene derivative as a ligand is a compound having excellent property as a catalyst for asymmetric synthesis. A method for producing the above mentioned benzene derivative by using 1,2-bis(phosphino)benzene as a stating material is described in PTL 1.
Also, a method for producing an optically active 1,2-bis(dialkylphosphino)benzene derivative is described in NPL 1. In above method, chromium 1,2-difluorobenzenetricarbonyl and borhium bis(ialkylphosphine) salt are used as a starting material.